c# - 为什么在 C# Exception 类中没有带有 1 个 Exception 参数的构造函数？

Question

System.Exception 类有 4 个构造函数:

public Exception();
public Exception(string message);
protected Exception(SerializationInfo info, StreamingContext context);
public Exception(string message, Exception innerException);

为什么没有这个构造函数？

public Exception(Exception innerException);

这是一个有用的地方。

我有一个静态方法来获取打开的连接:

public static DbConnection GetOpenConnection(string dataProvider, string connectionString) 
{
   DbConnection dbConnection = GetDbProviderFactory(dataProvider).CreateConnection();
   dbConnection.ConnectionString = connectionString;
   dbConnection.Open();
   return dbConnection;
}

我希望此方法在发生任何错误时抛出自定义异常 GetOpenConnectionException。

所以我创建了自定义异常GetOpenConnectionException:

public class GetOpenConnectionException : Exception
{
   public GetOpenConnectionException(string message) : base(message)
   {
   }
   public GetOpenConnectionException(string message, Exception innerException) : base(message, innerException)
   {
   }
}

由于 Exception 没有构造函数 public Exception(Exception innerException)，所以我不能在 GetOpenConnectionException 中包含此代码:

public GetOpenConnectionException(Exception innerException) : base(innerException)
{
}

所以我不得不这样编写 GetOpenConnection() 方法:

public static DbConnection GetOpenConnection(string dataProvider, string connectionString) 
{
   try 
   {
      DbConnection dbConnection = GetDbProviderFactory(dataProvider).CreateConnection();
      dbConnection.ConnectionString = connectionString;
      dbConnection.Open();
      return dbConnection;
   }
   catch (Exception e)
   {
      throw new GetOpenConnectionException("", e);
   }
}

我想要的是这样编写 GetOpenConnection() 方法:

public static DbConnection GetOpenConnection(string dataProvider, string connectionString) 
{
   try 
   {
      DbConnection dbConnection = GetDbProviderFactory(dataProvider).CreateConnection();
      dbConnection.ConnectionString = connectionString;
      dbConnection.Open();
      return dbConnection;
   }
   catch (Exception e)
   {
      throw new GetOpenConnectionException(e);
   }
}

这有意义吗？

Answer 1

   public GetOpenConnectionException(Exception innerException) : base("", innerException)
   {
   }